181910050_Maple G5_Textbook Integrated_Term1

Concept 3.2: Roman Numerals Think Pooja bought a clock, but found it difficult to read the time as she was not familiar with the numbers on it. Have you ever seen such numbers? Do you know what those numbers are? Recall We have already learnt about large numbers. Let us recall the concept by writing the number names of the given numbers using the Indian system. a) 42,52,572 – _____________________________________________________________________________ b) 8,40,178 – ______________________________________________________________________________ c) 4,79,42,121 – ___________________________________________________________________________ d) 8,01,00,971 – ____________________________________________________________________________ e) 3,24,56,712 – ____________________________________________________________________________ Apart from the Indian and the International systems of numeration, there is another system called the Roman numeral system. Let us learn about it. & Remembering and Understanding The numerals that we use in our day-to-day life are 1, 2, 3... These numbers are called the Hindu-Arabic numerals as they were developed in ancient India. They were spread to the other parts of the world by Arab traders. The Roman numerals were used in ancient Rome. It has seven letters of English with the help of which all other numbers are written. The Roman numeral system was followed in ancient Rome. Nowadays, Roman numerals are mainly used because of their historical importance. The Roman numbers are - I, V, X, L, C, D and M. Large Numbers 41 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 101 2/17/2018 4:03:46 PM

The following table shows the Roman numerals with their values in the Hindu-Arabic. Roman numerals I II III IV V VI VII VIII IX X Hindu-Arabic numerals 1 2 3 4 5 6 7 8 9 10 Roman numerals (symbols) I V X L CDM Hindu-Arabic numerals (values) 1 5 10 50 100 500 1000 We follow certain rules to read and write numerals in the Roman system. Rule Description Examples 1) A symbol can be repeated to a maximum II = 1 + 1 = 2 of three times. Repetition of numbers means XX = 10 + 10 = 20 addition. Only I, X, C and M can be repeated. CCC = 100 + 100 + 100 = 300 2) If a symbol is placed after the symbol of a XV = 10 + 5 = 15 greater value, the values are added. LXXX = 50 + 10 + 10 + 10 = 80 3) If a symbol is placed before the symbol of a MCC = 1000 + 100 + 100 = 1200 greater value, the smaller value is subtracted IV = 4 (5 – 1) from the greater one. IX = 9 (10 – 1) 4) I can be subtracted from V and X only. X can XC = 90 (100 – 10) be subtracted from L and C only. C can be IV = 4, IX = 9 subtracted from D and M only. XL = 40, XC = 90 CD = 400, CM = 900 Example 8: Write the Hindu-Arabic numerals for the given Roman numerals. Solution: a) CLXIX b) LXXVII c) DCL a) CLXIX = 100 + 50 + 10 + (10 – 1) = 169 Example 9: b) LXXVII = 50 + 10 + 10 + 5 + 1 + 1 = 77 Solution: c) DCL = 500 + 100 + 50 = 650 Write the Roman numerals for the given numbers. a) 160 b) 2950 c) 14 a) 160 = 100 + 50 + 10 = CLX b) 2950 = 1000 + 1000 + (1000 – 100) + 50 = MMCML c) 14 = 10 + (5 – 1)= XIV 42 2/17/2018 4:03:46 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 102

Example 10: Write the Roman numerals from 50 to 100 counting by 10s. Solution: Counting by 10s, we get 50, 60, 70, 80, 90 and 100. Roman numerals for these numbers are: L, LX, LXX, LXXX, XC and C respectively. Application Let us see a few real-life examples where we apply the knowledge of Roman numerals. Example 11: Read the following clocks and write the time they are showing using Hindu-Arabic numbers. a) b) Solution: a) The short (hour) hand has crossed IV. The Hindu-Arabic numeral for IV is 4. The long (minute) hand is on ‘V’ which is 5. So, it shows 25 minutes. Therefore, the time is 4:25. b) The short (hour) hand is at ‘II’. The Hindu-Arabic numeral for II is 2. The long (minute) hand is on ‘III’ which is 3. So, it shows 15 minutes. Therefore, the time is 2:15. Example 12: Rohit scores MDCLV marks in the first semester and MDCVIII marks in the second semester. Express Rohan’s total marks as Hindu-Arabic numerals. Solution: Rohit’s score in the first semester = MDCLV His score in the second semester = MDCVIII Hindu-Arabic numerals for the total marks are: MDCLV = 1000 + 500 + 100 + 50 + 5 = 1655 MDCVIII = 1000 + 500 + 100 + 5 + 1 + 1 + 1 = 1608 MDCLV + MDCVIII = 1655 + 1608 = 3263 Therefore, Rohit scored a total of 3263 marks. Large Numbers 43 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 103 2/17/2018 4:03:46 PM

Example 13: List out some real-life situations where Roman numerals are used. Solution: Some real-life situations where Roman numerals are used are: a) on wall clocks b) representation of classroom numbers. For example, Class IV-A, Class V-B and so on. c) section numbers in exam question papers d) chapter numbers in novels e) a fter people’s names. For example - John II and so on (used in Western countries very often). Higher Order Thinking Skills (H.O.T.S.) Consider the following examples based on large Roman numerals. Example 14: What is the Hindu-Arabic numeral for MDCLXVI? Solution: MDCLXVI = 1000 + 500 + 100 + 50 + 10 + 5 + 1 = 1666 Example 15: Which is the larger number between MDCLXXIV and MDCCLXXIX? Solution: MDCLXXIV = 1000 + 500 + 100 + 50 + 10 + 10 + (5 - 1) = 1674 MDCCLXXIX = 1000 + 500 + 100 + 100 + 50 + 10 + 10 + (10 - 1) = 1779 1779 > 1674. Thus, MDCCLXXIX is the larger number. Drill Time Concept 3.1: Indian and International Systems of Numeration 1) Write the successor and the predecessor of the following numbers. a) 62591 b) 59104 c) 18503 d) 70001 e) 28501 2) Separate the periods with commas and write the number names of the following in the Indian and International systems of numeration. a) 872492853 b) 658392759 c) 124654368 d) 765401954 e) 378954726 3) Fill in the blanks with >, < or =. a) 4,34,12,456 ______ 4,34,21,456 b) 2,31,98,896 ______ 6,87,98,541 c) 7,97,43,111 ______ 6,12,41,845 d) 1,67,91,941 ______ 1,76,19,149 44 2/17/2018 4:03:46 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 104

4) Arrange the numbers in the ascending and descending orders. a) 85714781, 57294769, 18372657 b) 17485729, 91845726, 75638462 c) 38593010, 75639205, 75927592 d) 10101010, 11010101, 10010101 Concept 3.2: Roman Numerals 5) Write the following in Roman numerals. a) 983 b) 804 c) 1481 d) 294 e) 1000 6) Write the following in the Hindu-Arabic numerals: a) CLXX b) LXVII c) DL d) MCML e) LXIX 7) Word problems a) T he population of Town A is 3832 and that of Town B is 6594. Which town has more population? Write it in Roman numeral. b) In a car race, Neha scores LXVI points and Raju scores XXV points. Who wins the race? Large Numbers 45 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 105 2/17/2018 4:03:46 PM

Chapter Addition and 4 Subtraction Let Us Learn About • a dding and subtracting large numbers. • column addition and subtraction of numbers. • a dding and subtracting large numbers in real life. Concept 4.1: Add and Subtract Large Numbers Think The total population of Pooja’s town is 1234567 out of which 876986 are adults. Pooja wanted to know the rest of the people number of in the town. Also, 25378 children were born the next year in that town. Pooja can find the total population of the town the next year. Do you know how to find the same? Recall Recall that we can add and subtract two or more numbers by writing them one below the other. This is called vertical or column addition. Let us solve the following to recall addition and subtraction. a) 283 + 115 b) 13652 +12245 c) 9685 – 5443 d) 47645 – 15322 e) 456789 – 23411 46 2/17/2018 4:03:46 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 106

& Remembering and Understanding In vertical or column addition, write the numbers one below the other, starting with the ones or the units place. In subtraction, write the bigger number at the top. Example 1: Solve the following: a) 403050906 + 444333222 b) 963271087 – 365842719 Solution: a) TC C TL L T Th Th H T O 1 403050906 +4 4 4 3 3 3 2 2 2 847384128 b) TC C TL L T Th Th H T O 8 15 12 12 6 10 10 7 17 /9 /6 /3 /2 /7 /1 /0 /8 /7 –3 6 5 8 4 2 7 1 9 597428368 When adding more than two numbers, we follow the same steps as above. Example 2: Solve: 3608926 + 1560863 + 5697528 Solution: C T L L T Th Th H T O 1111211 3608926 +1560863 +5697528 10867317 Addition and Subtraction 47 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 107 2/17/2018 4:03:46 PM

In some problems, we may have both addition and subtraction together. Let us a few some examples. Example 3: Simplify the following: a) 39154189 + 46673956 – 58127492 b) 742503 – 346280 + 210028 Solution: a) First add 39154189 and 46673956. Then subtract 58127492 from the sum. C T L L T Th Th H T O 1 1 111 39154189 +4 6 6 7 3 9 5 6 85828145 C T L L T Th Th H T O 7 15 7 10 14 /8 5/ 8 2 /8 1/ 4/ 5 –5 8 1 2 7 4 9 2 27700653 Therefore, 39154189 + 46673956 – 58127492 = 27700653. b) First subtract 346280 from 742503. Then, add 210028 to the difference. L T Th Th H T O L T Th Th H T O 6 13 12 4 10 1 1 742503 396223 / / / / / −3 4 6 2 8 0 +2 1 0 0 2 8 396223 606251 Therefore, 742503 – 346280 + 210028 = 606251. 48 2/17/2018 4:03:46 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 108

Application Let us consider a few real-life examples of addition and subtraction of large numbers. Example 4: Rathan’s father bought two houses, one for ` 9,56,000 and the other for ` 12,48,000. How much money did he spend altogether? By how much is the second house more expensive than the first? Solution: Cost of the 1st house = ` 9,56,000 Cost of the 2nd house = + ` 12,48,000 Amount Rathan’s father spent altogether = ` 22,04,000 Cost of the 2nd house = ` 12,48,000 Cost of the 1st house = – ` 9,56,000 Their difference = ` 2,92,000 Therefore, the second house was more expensive than the first house by ` 2,92,000. Example 5: A farmer spent ` 17,890 on fertilisers, ` 12,865 on seeds and ` 16,725 on irrigation. Find the total amount he spent on cultivation. Solution: Amount spent on fertilisers = ` 17,890 Amount spent on seeds = + ` 12,865 Amount spent on irrigation = + ` 16,725 Total amount spent = ` 47,480 Therefore, the amount spent on cultivation is ` 47,480. Higher Order Thinking Skills (H.O.T.S.) Let us now solve a few examples of addition and subtraction by rounding off the numbers. Example 6: Estimate 672406 – 573348 by rounding the numbers to the nearest hundreds. Solution: Rounding the given numbers to the nearest L T Th Th H T O hundreds, we get 672400 and 573300. 6 7 2 400 Their difference is 6,72,400 – 5,73,300. –5 7 3 3 0 0 Therefore, the estimated difference of the 0 9 9 100 given numbers is 99100. Addition and Subtraction 49 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 109 2/17/2018 4:03:46 PM

Example 7: The populations of cities A, B and C are 2871428, 3287654 and 1636741 Solution: respectively. Find the total population of the three cities. Round off the total population to the nearest thousands. TL L T Th Th H T O Population of City A = 28 7 1 428 Population of City B = +3 2 8 7 6 5 4 Population of City C = +1 6 3 6 7 4 1 Total population = 77 9 5 823 Rounding off to the nearest thousands, we get 77,96,000. Drill Time Concept 4.1: Add and Subtract Large Numbers 1) Solve: a) 96704319 + 32640521 b) 2680054 + 1098366 c) 3456786 + 2576987 d) 45678968 + 76894533 2) Solve: a) 89372051 – 76419265 b) 5396104 – 2278160 c) 9623175 – 8892431 d) 8235676 – 5629012 3) Word problems a) T here are 35,26,107 mango trees and 24,01,271 apple trees on a farm. How many trees are there in all? b) A car manufacturing company manufactured 5429756 cars in 2015 and 6721058 cars in 2016. How many more cars were manufactured in 2016 than in 2015? c) Smitha’s ribbon is 378214 cm long, and Keerthi’s ribbon is 387261 cm long. Whose ribbon is longer and by how much? d) A scooter costs ` 68925 and a car costs ` 923755. How much costlier is the car than the scooter? 50 2/17/2018 4:03:46 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 110

Chapter Multiplication 5 Let Us Learn About • p roperties of multiplication. • m ultiplying 4-digit and 5-digit by 2-digit and 3-digit numbers. • finding the missing numbers in the given product. • observing patterns in multiplication of numbers. Concept 5.1: Multiply Large Numbers Think Pooja’s mother bought 1750 kg of rice for the whole year at the price of ` 48 per kilogram. She asked Pooja to check if the bill is correct. How do you think Pooja can check it? Recall We have already learnt how to multiply a 4-digit number by a 1-digit number. Let us recall the basic concepts of multiplication. Properties of Multiplication Identity Property: For any number ‘a’, a × 1 = 1 × a = a. 1 is called the multiplicative identity. For example, 213 × 1 = 1 × 213 = 213. NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 111 51 2/17/2018 4:03:46 PM

Zero Property: For any number ‘a’, a × 0 = 0 × a = 0. For example, 601 × 0 = 0 × 601 = 0. Commutative Property: If ‘a’ and ‘b’ are any two numbers, then a × b = b × a. For example, 25 × 7 = 175 = 7 × 25. Associative Property: If ‘a’, ‘b’ and ‘c’ are any three numbers, then a × (b × c) = (a × b) × c. For example, 3 × (4 × 5) = (3 × 4) × 5 3 × 20 = 12 × 5 60 = 60 Let us answer the following to revise the the multiplication of 4-digit numbers. a) Th H T O b) Th H T O c) Th H T O 3234 1274 4567 ×2 ×8 ×5 d) Th H T O e) Th H T O f) Th H T O 5674 3120 4372 ×3 ×4 ×8 & Remembering and Understanding Multiplication of large numbers is the same as multiplication of 4-digit or 5-digit numbers by 1-digit numbers. If an ‘x’-digit number is multiplied by a ‘y’-digit number, then their product is not more than a ‘(x + y)’- digit number. Let us solve some examples of multiplication of large numbers. 52 2/17/2018 4:03:46 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 112

Example 1: Find these products. a) 2519 × 34 b) 4625 × 17 Solution: a) T Th Th H T O b) T Th Th H T O 12 23 413 2519 4625 ×34 ×17 11 1 0 0 7 6 → 2519 × 4 ones 3 2 3 7 5 → 4625 × 7ones + 7 5 5 7 0 → 2519 × 3 tens +4 6 2 5 0 → 4625 × 1 tens 8 5 6 4 6 → 2519 × 34 7 8 6 2 5 → 4625 × 17 Example 2: Find the product of 3768 and 407. Solution: T L L T Th Th H T O Here we can skip 323 the step ‘3768 × 0’ but, add one more zero in 545 3768 tens place while ×407 multiplying by 1 hundreds digit. 2 6 3 7 6 → 3768 × 7 ones + 1 5 0 7 2 0 0 → 3768 × 4 hundreds 1 5 3 3 5 7 6 → 3768 × 407 Example 3: Estimate the number of digits in the product of 58265 and 73. Then multiply and verify your answer. Solution: The number of digits in the multiplicand 58265 is five. The number of digits in the multiplier 73 is two. Total number of digits is seven. Therefore, the product of 58265 and 73 should not have more than seven digits. Multiplication 53 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 113 2/17/2018 4:03:46 PM

T L L T Th Th H T O 5 143 Example 4: 2 11 Solution: 5 8265 ×73 11 11 1 7 4 7 9 5 → 58265 × 3 ones + 4 0 7 8 5 5 0 → 58265 × 7 Tens 4 2 5 3 3 4 5 → 58265 × 73 The number of digits in the product 4253345 is 7. Hence, verified. Find the product of 24367 and 506. T L L T Th Th H T O 2 133 2 244 2 4367 ×506 1 1 4 6 2 0 2 → 24367 × 6 ones + 1 2 1 8 3 5 0 0 → 24367 × 5 hundreds 1 2 3 2 9 7 0 2 → 24367 × 506 Application We use multiplication of numbers in many real-life situations. Let us see a few examples. 54 2/17/2018 4:03:46 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 114

Example 5: A farmer has 6350 acres of mango farm. If he L T Th Th H T O needs 58 kg of fertiliser for each acre, how 12 Solution: many kilograms of fertiliser does he need in all? Quantity of fertiliser required for 1 acre of farm 24 Example 6: Solution: = 58 kg 6350 Quantity of fertiliser required for 6350 acres ×58 of farm = 6350 × 58 kg 1 Example 7: Solution: = 368300 kg 5 0800 +3 1 7 5 0 0 3 6 8300 The cost of one fridge is ` 9528. What is the cost of 367 such fridges? Cost of one fridge = ` 9528 Cost of 367 fridges = ` 9528 × 367 T L L T Th Th H T O 12 314 315 9528 ×367 1 1 1 11 6 6696 + 5 7 1680 + 2 8 5 8400 3 4 9 6776 Therefore, the cost of 367 fridges is ` 3496776. A clothier sells different suiting and shirting and earns ` 48657 per day. How much does he earn in one week? L T Th Th H TO 6 43 4 Amount earned by a clothier in one day = ` 48657 4 86 57 ×7 Amount earned by him in one week 3 4 05 99 (7 days) = ` 48657 × 7 Therefore, amount earned by the clothier in a week is ` 340599. Multiplication 55 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 115 2/17/2018 4:03:47 PM

Higher Order Thinking Skills (H.O.T.S.) Let us see a few more real-life examples involving multiplication of large numbers. Example 8: A cloth mill produces 8573 m of cloth in a day. How many metres of cloth can it produce in January, if there are six holidays in the month? Solution: Length of the cloth produced by a cloth mill in a day = 8573 m In January, if six days are holidays, the number of working days = 31 – 6 = 25 Length of cloth produced in 25 days = 8573 m × 25 = 214325 m Example 9: Find the missing numbers in the given product. T Th Th H T O 3417 ×63 1 21 + 0 5 20 21 271 Solution: T Th Th H T O 3417 ×63 1 0251 +2 0 5 0 2 0 2 1 5271 Example 10: Observe the pattern and write the next two terms. 4×4=16 34 × 34=1156 334×334=111556 ---------------------------------- ---------------------------------- 56 2/17/2018 4:03:47 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 116

Solution: The next two terms in the given pattern are 3334×3334=11115556 33334×33334=1111155556 Drill Time Concept 5.1: Multiply Large Numbers 1) Solve: a) 12345 × 7 b) 90962 × 113 c) 3578 × 575 d) 8869 × 450 e) 5124 × 52 2) Word problems a) A cloth factory produces 32674 m of cloth in a week. How many metres of cloth can the factory produce in 6 weeks? b) A table costs ` 1354. Find the cost of 73 such tables. c) Find the product of the largest 4-digit number and the largest 2-digit number. d) There are 5606 bags of rice in a godown. If each bag weighs 62 kg, what is the total weight of the bags of rice? Multiplication 57 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 117 2/17/2018 4:03:47 PM

Chapter Division 6 Let Us Learn About • d ividing 5-digit by 1-digit and 2-digit numbers. • rules of divisibility • finding prime and composite numbers. • factors, multiples, H.C.F. and L.C.M. of numbers. • prime factorisation of numbers. Concept 6.1: Divide Large Numbers Think Pooja’s brother saved ` 12500 in two years. He saved an equal amount every month. Pooja wanted to find his savings per month. How do you think Pooja can find that? Recall In Class 4, we have learnt dividing a 4-digit number by a 1-digit number. Let us now revise this concept with a few example. Divide: a) 3165 ÷ 3 b) 5438 ÷ 6 c) 2947 ÷ 7 d) 7288 ÷ 4 e) 1085 ÷ 5 58 2/17/2018 4:03:47 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 118

& Remembering and Understanding Dividing a 5-digit number by a 1-digit number is the same as dividing a 4-digit number by a 1-digit number. Example 1: Divide: a) 12465 ÷ 5 b) 76528 ÷ 4 Solution: a) 2493 b) 19132 )5 12465 )4 76528 −10 −4 24 36 − 20 − 36 46 05 − 45 − 04 15 12 − 15 − 12 0 08 −8 0 Let us now divide a 5-digit number by a 2-digit numbers. Example 2: Divide: 21809 ÷ 14 Solution: Write the dividend and the divisor as Divisor Dividend Steps Solved Solve these 14 21809 Step 1: Guess the quotient by )20 53174 dividing the two leftmost digits by 14 × 1 = 14 the divisor. Find the multiplication fact which 14 × 2 = 28 has the dividend and the divisor. 14 < 21 < 28 So,14 is the number to be subtracted from 21. Division 59 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 119 2/17/2018 4:03:47 PM

Steps Solved Solve these Step 2: Write the factor other than Write 1 in the quotient and )13 34567 the dividend and the divisor as 14 below 21, and subtract. the quotient. Then bring down the next number in the dividend. 1 14 21809 −14 78 Step 3: Repeat steps 1 and 2 until 1557 )15 45675 all the digits of the dividend are brought down. )14 21809 Stop the division when the − 14 remainder < divisor. 78 − 70 80 − 70 109 − 98 11 Step 4: Write the quotient and the Quotient = 1557 remainder. The remainder must Remainder = 11 always be less than the divisor. Checking for the correctness of division: We can check if our division is correct using a multiplication fact of the division. Step 1: Compare the remainder and the divisor. Step 2: Check if (Quotient × Divisor) + Remainder = Dividend 60 2/17/2018 4:03:47 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 120

Let us now check if our division in example 2 is correct or not. Step 1: Remainder < Divisor Dividend = 21809 Divisor = 14 Quotient = 1557 Remainder = 11 Step 2: (Quotient × Divisor) + 11 < 14 (True) Remainder = Dividend 1557 × 14 + 11 = 21809 21798 + 11 = 21809 21809 = 21809 (True) Note: 1) If remainder > divisor, the division is incorrect. 2) If (Quotient × Divisor) + Remainder is not equal to Dividend, the division is incorrect. Application Let us now see a few real-life examples of division of large numbers. Example 3: A machine produces 48660 pens in the month of June. How many pens does it Solution: produce in a day? 1622 Number of days in the month of June = 30 )30 48660 Number of pens produced in the month = 48660 − 30 Number of pens produced in a day = 48660 ÷ 30 186 − 180 66 − 60 60 − 60 Therefore, the machine produces 1622 pens in a day. 00 Division 61 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 121 2/17/2018 4:03:47 PM

Example 4: Vijay bought 15375 sheets of paper for 35 students of his class. If the sheets are Solution: distributed equally, how many sheets would each student get? Will any sheets remain? = 15375 439 Total number of sheets )35 15375 Number of students = 35 -140 137 Number of sheets each student gets = 15375 ÷ 35 - 105 Therefore, the number of sheets each student gets = 439 325 Number of sheets that remain = 10 - 315 Rules of divisibility 10 Divisibility rules help us to find the numbers that divide a given number exactly. By using them, we can find the factors of a number, without actually dividing it. Divisor Rule Examples 2 The ones digit of the given number must be 0, 2, 4, 6 10, 42, 56, 48, 24 3 or 8. 4 The sum of the digits of the given number must be 36 (3 + 6 = 9) divisible by 3. 48 (4 + 8 = 12) 5 1400, 3364, 2500, 7204 The number formed by the last two digits of the given number must be divisible by 4 or both the digits 230, 375, 100, 25 must be zero. The ones digit of the given number must be 0 or 5. 6 The number must be divisible by both 2 and 3. 36, 480, 1200 9 The sum of the digits of the given number must be 36 (3 + 6 = 9) divisible by 9. 144 (1 + 4 + 4 = 9) 10 The ones digit of the given number must be 0. 300, 250, 5670 Let us now apply the divisibility rules to check if a given number is divisible by 2, 3, 4, 5, 6, 9 or 10. Example 5: Which of the numbers 2, 3, 4, 5, 6, 9 and 10 divide 42670? Solution: To check if 2, 3, 4, 5, 6, 9 or 10 divide 42670, apply their divisibility rules. Divisibility by 2: The ones place of 42670 has 0. So, it is divisible by 2. Divisibility by 3: The sum of the digits of 42670 is 4 + 2 + 6 + 7 + 0 =19. 19 is not divisible by 3. So, 42670 is not divisible by 3. 62 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 122 2/17/2018 4:03:47 PM

Divisibility by 4: The number formed by the digits in the last two places of 42670 is 70, which is not exactly divisible by 4. So, 42670 is not divisible by 4. Divisibility by 5: The ones place of 42670 has 0. So, it is divisible by 5. Divisibility by 6: 42670 is divisible by 2 but not by 3. So, it is not divisible by 6. Divisibility by 9: The sum of the digits of 42670 is 4 + 2 + 6 + 7 + 0 = 19, which is not divisible by 9. So, 42670 is not divisible by 9. Divisibility by 10: The ones place of 42670 has 0. So, it is divisible by 10. Hence, the numbers that divide 42670 are 2, 5, and 10. Example 6: Complete this table. Number 2 3 Divisible by 9 10 456 464 390 3080 4500 Solution: Apply the divisibility rules to check if the given numbers are divisible by the given factors. Number 2 3 Divisible by 9 10 456 464        390        3080        4500        Higher Order Thinking Skills (H.O.T.S.) Let us see a few examples where we use the of divisibility rules in some real-life situations. Example 7: In a nursery, there are 4056 plants. How many can be planted in each row, if there are 2, 3, 4, 5, 6, 9 or 10 rows? Will some plants be left over in any of the arrangements? Solution: Number of plants in the nursery = 4056 4056 is divisible exactly by: Division 63 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 123 2/17/2018 4:03:47 PM

2 (since the ones digit is 6), 3 (since 4 + 0 + 5 + 6 = 15), 4 (since 56 is divisible by 4) and 6 (since 4056 is divisible by 2 and 3). Example 8: So, we can arrange 4056 plants in rows of 2, 3, 4 or 6. Solution: Since 4056 is not exactly divisible by 5, 9 and 10, some plants remain if they are arranged in 5, 9 or 10 rows. Dilip shares 350 stamps with his friends. If he gives 2, 3, 5 or 10 stamps to each friend, will all the stamps be shared? Number of stamps Dilip shares = 350 If Dilip shares 2, 5 or 10 stamps each, all the stamps will be distributed as 2, 5 and 10 divide 350 exactly. If he gives 3 stamps to each of his friends, some stamps remain as 350 is not exactly divisible by 3. Concept 6.2: Factors and Multiples Think Pooja learnt to find factors of a given number using multiplication and division. She wants to know the name given to the product obtained when we multiply numbers by counting. Do you know the name given to such products? Recall The numbers that divide a given number exactly are called the factors of that number. In other words, the numbers, which when multiplied ,give a product are called the factors of the product. For example, in 12 × 9 = 108, the numbers 12 and 9 are called the factors of 108. The number 108 is called the product of 12 and 9. 64 2/17/2018 4:03:47 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 124

Complete the multiplication table of 8. 8×1=8 8×2= 8×3= 8×4= 8 × 5 = 40 8 × 6 = 48 8×7= 8 × 8 = 64 8×9= 8 × 10 = & Remembering and Understanding The products obtained when a number is multiplied by 1, 2, 3, 4, 5 …. are called the multiples of that number. In a multiplication table, a number is multiplied by the numbers 1, 2, 3, 4, 5 and so on till 10. In the multiplication table of 8, the products obtained are 8, 16, 24, 32, 40 and so on till 80. These are called the first ten multiples of 8. Similarly, a) 2, 4, 6, 8, 10, 12 … are the multiples of 2. b) 5, 10, 15, 20, 25, 30… are the multiples of 5. Let us now find the factors of some numbers. Factors of numbers from 1 to 10: Number Factors Number of Number Factors Number of factors factors 1 1 1 6 1, 2, 3, 6 4 2 1, 2 2 7 1, 7 2 3 1, 3 2 8 4 4 1, 2, 4 3 9 1, 2, 4, 8 3 5 1, 5 2 10 1, 3, 9 4 1, 2, 5, 10 From the given table, we observe that: 1) The number 1 has only one factor. 2) The numbers 2, 3, 5 and 7 have only two factors (1 and themselves) 3) The numbers 4, 6, 8, 9 and 10 have three or four factors (more than two factors). Note: 1) The numbers that have only two factors (1 and themselves) are called prime numbers 2) The numbers that have more than two factors are called composite numbers. 3) The number 1 has only one factor. So, it is neither prime nor composite. Division 65 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 125 2/17/2018 4:03:47 PM

Sieve of Eratosthenes Eratosthenes was a Greek mathematician. He created the sieve of Eratosthenes, to find prime numbers between any two given numbers. Steps to find prime numbers between 1 and 100 using the sieve of Eratosthenes: Step 1: Prepare a grid of numbers from 1 to 100. Step 2: Cross out 1 as it is neither prime nor composite. Step 3: Circle 2 as it is the first prime number. Then cross out all the multiples of 2. Step 4: Circle 3 as it is the next prime number. Then cross out all the multiples of 3. Step 5: Circle 5 as it is the next prime number. Then cross out all the multiples of 5. Step 6: C ircle 7 as it is the next prime number. Then cross out all the multiples of 7. Continue this process till all the numbers between 1 and 100 are either circled or crossed out. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 The circled numbers are the prime numbers and the crossed out numbers are the composite numbers. 66 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 126 2/17/2018 4:03:47 PM

There are 25 prime numbers between 1 and 100. These are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89 and 97. Note: 1) All prime numbers (except 2) are odd. 2) 2 is the only even prime number. Example 9: Find the factors: a) 16 b) 40 Solution: a) To find the factors of a given number, express it as a product of two numbers as shown: 16 = 1 × 16 =2×8 =4×4 Then write each factor only once. So, the factors of 16 are 1, 2, 4, 8 and 16. b) 40 = 1 × 40 = 2 × 20 = 4 × 10 =5×8 So, the factors of 40 are 1, 2, 4, 5, 8, 10, 20 and 40. Example 10: Find the common factors of 10 and 15. Solution: 10 = 1 × 10 and 10 = 2 × 5 So, the factors of 10 are 1, 2, 5 and 10. 15 = 1 × 15 and 15 = 3 × 5 So, the factors of 15 are 1, 3, 5 and 15. Therefore, the common factors of 10 and 15 are 1 and 5. We can find the factors of a number by multiplication or by division. Example 11: Find the factors of 30. Solution: Factors of 30 Using multiplication 1 × 30 = 30 2 × 15 = 30 3 × 10 = 30 Division 67 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 127 2/17/2018 4:03:47 PM

5 × 6 = 30 The numbers multiplied to obtain the given number as the product are called its factors. So, the factors of 30 are 1, 2, 3, 5, 6, 10, 15 and 30. Using division 30 ÷ 1 = 30 30 ÷ 2 = 15 30 ÷ 3 = 10 30 ÷ 5 = 6 The different quotients and divisors of the given number are its factors. So, the factors of 30 are 1, 2, 3, 5, 6, 10, 15 and 30. Facts on Factors 1) 1 is the smallest factor of a number. 2) 1 is a factor of every number. 3) A number is the greatest factor of itself. 4) Every number is a factor of itself. 5) The factor of a number is less than or equal to the number itself. 6) Every number (other than 1) has at least two factors – 1 and the number itself. 7) The number of factors of a number is limited. Let us now find the multiples of some numbers. Example 12: Find the first six multiples: a) 9 b) 15 c) 20 Solution: The first six multiples of a number are the products when the number is multiplied by 1, 2, 3, 4, 5 and 6. a) 1 × 9 = 9, 2 × 9 = 18, 3 × 9 = 27, 4 × 9 = 36, 5 × 9 = 45, 6 × 9 = 54. So, the first six multiples of 9 are 9, 18, 27, 36, 45 and 54. Now, complete these: b) 1 × 15 = 15, ___ × ___ = ____, ___ × ___ = ___, ___ × ____ = ____, ____ × ___ = ____, _____ × _____ = ____. So, the first six multiples of 15 are ____, ____, ____, ____, ____ and ____. 68 2/17/2018 4:03:47 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 128

c) 1 × 20 = 20, ___ × ___ = ____, ___ × ___ = ___, ___ × ____ = ____, ____ × ___ = ____, _____ × _____ = ____. So, the first six multiples of 20 are ____, ____, ____, ____, ____ and ____. Example 13: Find three common multiples of 10 and 15. Solution: Multiples of 10 are 10, 20, 30, 40, 50, 60, 70, 80, 90,100,…. Multiples of 15 are 15, 30, 45, 60, 75, 90, 105,…. Therefore, the first three common multiples of 10 and 15 are 30, 60 and 90. Facts on Multiples 1) Every number is a multiple of itself. 2) Every number is a multiple of 1. 3) A number is the smallest multiple of itself. 4) The multiples of a number are greater than or equal to the number itself. 5) The number of multiples of a given number is unlimited. 6) The largest multiple of a number cannot be determined. Application Finding factors and multiples helps us to find the Highest Common Factor (H.C.F.) and the Least Common Multiple (L.C.M.) of the given numbers. Highest Common Factor (H.C.F.): The highest common factor of two or more numbers is the greatest number that divides the numbers exactly (without leaving a remainder). Least Common Multiple (L.C.M.): The least common multiple of two or more numbers is the smallest number that can be divided by the numbers exactly (without leaving a remainder). Example 14: Find the highest common factor of 12 and 18. Solution: 12 = 1 × 12, 12 = 2 × 6 and 12 = 3 × 4 So, the factors of 12 are 1, 2, 3, 4, 6 and 12. 18 = 1 × 18, 18 = 2 × 9 and 18 = 3 × 6 So, the factors of 18 are 1, 2, 3, 6, 9 and 18. The common factors of 12 and 18 are 1, 2, 3 and 6. Therefore, the highest common factor of 12 and 18 is 6. Division 69 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 129 2/17/2018 4:03:47 PM

Example 15: Find the least common multiple of 12 and 18. Solution: The multiples of 12 are 12, 24, 36, 48, 60, 72… The multiples of 18 are 18, 36, 54, 72… The common multiples of 12 and 18 are 36, 72… Therefore, the least common multiple of 12 and 18 is 36. Higher Order Thinking Skills (H.O.T.S.) Let us now complete these tables of H.C.F. and L.C.M. of the given numbers. Example 16: Complete the H.C.F. table given. Some H.C.F. values are given for you. Numbers 10 12 18 30 2 2 3 6 12 15 15 Solution: Numbers 10 12 18 30 2 2222 3 12 1333 15 2 12 6 6 5 3 3 15 Example 17: Complete the L.C.M. table given. Some L.C.M. values are given for you. Numbers 10 12 18 30 2 18 3 12 12 15 30 Solution: Numbers 10 12 18 30 2 10 12 18 30 3 30 12 18 30 12 60 12 36 60 15 30 60 90 30 70 2/17/2018 4:03:47 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 130

Example 18: How many prime and composite numbers are there between 35 and 55? Solution: The prime numbers between 35 and 55 are 37, 41, 43, 47 and 53 which are five in number. There are 19 numbers between 35 and 55, of which five are prime. So, 19 – 5 = 14 numbers are composite. Concept 6.3: H.C.F. and L.C.M. Think Pooja now knows prime and composite numbers. She wants to know a simple way to find H.C.F. and L.C.M. of two numbers. Do you know any simple method for the same? Recall We have learnt about prime and composite numbers and the definitions of H.C.F. and L.C.M. We first find the factors of the given numbers. The highest common number among them gives the H.C.F. of the given numbers. Likewise, we can find the multiples of the given numbers. The least common among them gives the L.C.M. of the given numbers. Let us revise the concept by finding the common factors of the following pairs of numbers. a) 12, 9 b) 15, 10 c) 30, 12 d) 24, 16 e) 35, 21 f) 36, 54 & Remembering and Understanding Prime numbers have only 1 and themselves as their factors. Composite numbers have more than two factors. So, composite numbers can be expressed as the products of their prime numbers or composite numbers. For example, 5 = 1 × 5; 20 = 1× 20 9 = 1 × 9, = 2 × 10 = 3 × 3; =4×5 We can express all composite numbers as the products of prime factors. Division 71 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 131 2/17/2018 4:03:47 PM

Expressing a number as a product of prime numbers is called prime factorisation. To prime factorise a number, we use factor trees. Let us see a few examples to understand this better. Example 19: Prime factorise 36. Solution: To carry out the prime factorisation of 36, draw a factor tree as shown. Step 1: Express the given number as a product of two factors. One of these factors is the least number (other than 1) that can divide it. The second factor may be prime or composite. Step 2: If the second factor is a composite number, express it as a product of two factors. One of these factors is the least number (other than 1) that can divide it. The second factor may be prime or composite. Step 3: Repeat the process till the factors 36 Step 4: cannot be split further. In other words, repeat the process till the factors do 2 × 18 not have any common factor other × 9 than 1. 2 × 2 Then write the given number as the product of all the prime numbers. 2 × 2 × 3 × 3 Therefore, the prime factorisation of 36 is 2 × 2 × 3 × 3. Note: A factor tree must be drawn using a prime number as one of the factors of the number at each step. Example 20: Prime factorise 54. Solution: Prime factorisation of 54 using a factor tree: 54 2 × 27 2 × 3 × 9 1 × 3 × 3 × 3 Therefore, the prime factorisation of 54 is 2 × 3 × 3 × 3. 72 2/17/2018 4:03:47 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 132

Application Finding H.C.F. using prime factorisation Let us now find the H.C.F. of two numbers using prime factorisation. Example 21: Find the H.C.F. of 48 and 54 by the prime factorisation method. Solution: The prime factorisation of 48 is 2 × 2 × 2 × 2 × 3. The prime factorisation of 54 is 2 × 3 × 3 × 3. Therefore, the H. C. F of 48 and 54 is 2 × 3 which is 6. Finding L.C.M. using prime factorisation Let us now find the L.C.M. of two numbers using prime factorisation. Example 22: Find the L.C.M. of 18 and 24 by prime factorisation method. Solution: Prime factorisation of 18 is 2 × 3 × 3. Prime factorisation of 24 is 2 × 2 × 2 × 3. Therefore, the L.C.M. of 18 and 24 is 2 × 3 × 2 × 2 × 3 = 72. Higher Order Thinking Skills (H.O.T.S.) Let us now solve a few examples involving the H.C.F. and L.C.M. of three numbers. First, express the numbers as products of prime factors, and then find their H.C.F. Example 23: Find the H.C.F. of 14, 28 and 35. Solution: Prime factorisation of 14 is 2 × 7. Prime factorisation of 28 is 2 × 2 × 7. Prime factorisation of 35 is 5 × 7. Therefore, the H.C.F. of 14, 28 and 35 is 7. Example 24: Find the L.C.M. of 14, 28 and 35. Solution: Prime factorisation of 14 is 2 × 7. Prime factorisation of 28 is 2 × 2 × 7. Prime factorisation of 35 is 5 × 7. Therefore, the L.C.M. of 14, 28 and 35 is 2 × 2 × 7 × 5 = 140. Division 73 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 133 2/17/2018 4:03:47 PM

Drill Time Concept 6.1: Divide Large Numbers 1) Divide: a) 43243 by 23 b) 50689 by 14 c) 52043 by 18 d) 21861 by 5 e) 72568 by 4 2) Word problems a) Which of the numbers among 2, 3, 4, 5, 6, 9 and 10 divide 893205? b) Which of the numbers among 2, 3, 4, 5, 6, 9 and 10 divide 24688? Concept 6.2: Factors and Multiples 3) Find the factors of the following: a) 36 b) 49 c) 100 d) 120 e) 91 4) Find the multiples of the following as given in the brackets: a) 7 (First 8) b) 15 (First 5) c) 100 (First 10) d) 25 (First 4) e) 30 (First 6) 5) Find the highest common factor of the following pairs of numbers. a) 12, 20 b) 15, 27 c) 24, 48 d) 16, 64 e) 30, 45 6) Find the least common multiple of the following pairs of numbers. a) 8, 10 b) 12, 15 c) 16, 20 d) 22, 33 e) 15, 30 Concept 6.3: H.C.F. and L.C.M. 7) Prime factorise the following using the factor tree method. a) 108 b) 128 c) 56 d) 48 e) 63 8) Solve: a) Find the L.C.M. of 32 and 56 by prime factorisation. b) Find the H.C.F. of 25 and 75 by prime factorisation. c) Find the H.C.F. of 96 and 108 by prime factorisation. d) Find the L.C.M. of 45 and 75 by prime factorisation. 74 2/17/2018 4:03:48 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 134

EVS-I (SCIENCE) TERM 1 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 135 2/17/2018 4:03:48 PM

Preface IMAX partners with schools, supporting them with learning materials and processes that are all crafted to work together as an interconnected system to drive learning. IMAX presents the latest version of the Maple series – updated and revised after considering the perceptive feedback and comments shared by our experienced reviewers and users. Designed specifically for state board schools, the Maple series endeavours to be faithful to the spirit of the State Curriculum Framework and the National Curriculum Framework (NCF) 2005. Therefore, our books strive to ensure inclusiveness in terms of gender and diversity in representation, catering to the heterogeneous Indian classroom. The larger aim of the NCF 2005 regarding EVS-I teaching is to acknowledge and address the dynamic nature of EVS-I by focusing on the development of skills to acquire and process information scientifically. The Maple EVS-I textbooks and workbooks for state board schools offer the following features:  Interactive content that engages students through a range of open- ended questions that build curiosity and initiate scientific exploration  Opportunities for experimentation, analysis and synthesis of ideas and concepts  Exposure to locally relevant environmental problem solving  Effective use of visual elements to enable learning of structures, processes and phenomena  A focus on EVS-I specific vocabulary building  Integrated education of values and life skills  Promotion of participatory and contextualised learning through the engagement of all relevant stakeholders in the learning process Overall, the IMAX Maple EVS-I textbooks, workbooks and teacher companion books aim to enhance the development of scientific temper along with the inculcation of healthy habits, skills and values that promote environmentally sensitive and culturally responsive democratic citizenship among students. – The Authors NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 136 2/17/2018 4:03:48 PM

Textbook Features Let Us Learn About Think Contains the list of learning objectives to Introduces the concept/subtopic and be achieved in the lesson arouses curiosity among students Understanding Remembering • Explains the aspects in detail that form Introduces new concepts to build on the basis of the concept the prerequisite knowledge/skills required to understand and apply the objective • Includes elements to ensure that of the topic students are engaged throughout Application Amazing Facts Connects the concept to real-life Fascinating facts and trivia related to situations by enabling students to apply the concept what has been learnt through the practice questions Higher Order Thinking Skills (H.O.T.S.) Encourages students to extend the concept learnt to advanced application scenarios Inside the Lab Provides for hands-on experience with creating, designing and implementing something innovative and useful NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 137 2/17/2018 4:03:48 PM

Contents 5Class 1 Muscular System���������������������������������������������������������������������������������������������������������� 1 2 Respiratory System������������������������������������������������������������������������������������������������������� 6 3 Nervous System������������������������������������������������������������������������������������������������������������ 9 4 Floats, Sinks and Mixes���������������������������������������������������������������������������������������������� 13 Inside the Lab – A������������������������������������������������������������������������������������������������������������� 17 Activity A1: Respiratory System Activity A2: Water as a Universal Solvent 5 Fruits and Seeds���������������������������������������������������������������������������������������������������������� 19 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 138 2/17/2018 4:03:48 PM

Lesson Muscular System 1 Let Us Learn About R muscles and the muscular system. u the functions of our muscles. a keeping our muscles healthy. h injuries related to muscles. Think While playing kabaddi with friends, Raghav injured his hand. His mother took him to a doctor. After checking his hand, the doctor said that it was a muscle injury and not a fracture. Raghav wondered what a muscle is and how it looked. Do you know about muscles? Remembering Make a fist and fold your hand at the elbow. Touch your upper arm with your other hand. Can you feel a soft and spongy material inside? Now, while still touching it with your fingers, slowly unfold the arm. Can you feel some movement inside the upper arm? These are muscles. Muscles are present all over our body. All the muscles together form the organ system called the muscular system. NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 139 1 2/17/2018 4:03:49 PM

According to the place where muscles are, they can be of three different types. They are: 1) Skeletal muscles: These are muscles which are attached to the bones. They pull the bones to make movements of hands and legs. We can control these muscles. 2) Smooth muscles: These are muscles on the walls of internal organs. For example, the muscles of stomach, intestines and so on. They are not attached to the bones. 3) Heart (Cardiac) muscles: These muscles are found only in the heart. Both the smooth and the heart muscles are not the human muscular system controlled by us. They work throughout the day on their own with the help of our brain. The three types of muscles skeletal muscles smooth muscles cardiac muscles Understanding Why do we have muscles in our body? The main function of the muscular system is the movement of different body parts. Try this: Make a fist. Tighten the fist. And loosen the fist. What do you feel? We can feel the muscles moving. They help in movement by becoming tight and loose like a spring or a rubber band. 2 2/17/2018 4:03:49 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 140

For example, to bend our hand, some muscles will become tight and some will become loose. Let us see some movements using muscles. a) The muscles attached to the bones help in movements of muscles becoming tight hands, legs and so on. Example: walking, running, writing and loose and so on b) Heart muscles help the heart to pump blood. c) Muscles around the lungs (rib cage muscles and a dome shaped muscle at the base of the chest cavity) help in breathing. When these muscles contract and relax, air flows in and out of the lungs. d) Smooth muscles of the stomach and intestines help in the movement and digestion of food. muscles help in muscles help to breathe muscles help movement in digestion e) D id you know that your lips and tongue are made up of muscles too? These muscles help us while talking and eating. f) Muscles help us to maintain the body posture. They help to keep us upright and erect. g) Muscles also provide heat to our body. When we lips and tongue are muscles vibrate in feel cold, our muscles vibrate rapidly to generate made of muscles cold weather body heat. This is the reason why we shiver when we feel cold. Application Muscles are an important part of our body, so they should be healthy. Healthy food and regular exercise make the muscles stronger and healthier. Muscular System 3 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 141 2/17/2018 4:03:49 PM

We should follow these practices to keep our muscles healthy and strong: 1) Warm up → exercise → cool down: Exercise for 15–20 minutes every day. Warm up the different body parts with a brisk walk or a light jog before starting with exercise. After the exercise, let the body cool down slowly. Doing warm up before exercise prepares the body for the exercise. This is because the heart pumps more blood to the muscles. So, the chance of injury due to exercising is reduced. brisk walk light jog 2) Stretch: Stretch all body parts every day. It improves the strength of muscles. 3) Drink a lot of water: We should drink at least two litres of water every day. It keeps the muscles and other internal organs healthy. 4) Balanced diet: Our food helps our stretching all parts of body muscles strengthen, repair themselves and function properly. It is important to include all the nutrients like minerals and vitamins in our diet. Amazing Facts Our heart muscles never get to rest. They work non-stop till we die! Higher Order Thinking Skills (H.O.T.S.) We often hear of sportspersons getting injured. Do you know that most of their injuries are related to muscles? Let us learn about some common muscle injuries. 4 2/17/2018 4:03:49 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 142

1) Strain: When a muscle has muscle strain in different ice pack on sprained stretched too much, it causes parts of the body leg muscle strain. For example, if we lift something too heavy like a big bucket of water, we might strain our muscle. It also happens when a muscle is used too much without rest. The treatment for strain includes applying an ice pack to the affected area. 2) Cramp: Sometimes a painful tightening of a muscle happens suddenly. This is a cramp. For example, if we play in warm or hot weather without drinking enough water, we get a cramp. It lasts from a few seconds to several minutes. It often occurs in the legs. Treatment for cramps is the massage of the affected area. 3) Bruises: Bruises happen if our body cramp in leg hits any hard object. The area swells up. It forms a red mark that is painful, and movement becomes difficult. For example, when we fall from a bicycle or get hurt while playing football, we get bruises. example of bruises while playing Children mostly get their knees and elbows bruised while playing. We should wash the bruise properly and put a bandage on it. Do you know what a hamstring injury is? Find out. (Hint: Hamstrings are a group of leg muscles.) bandage on bruises hamstring muscles Muscular System 5 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 143 2/17/2018 4:03:49 PM

Lesson Respiratory System 2 Let Us Learn About r respiration and the respiratory system. U steps of respiration. A breathing rate and how blowing air can warm up or cool down things. H the importance of a stethoscope. Think Hold your finger under your nose. What do you feel on your finger? Remembering Have you ever noticed someone breathe? What does the person do? He or she breathes in and breathes out. This continues throughout the day. Taking in oxygen from the air and giving out carbon dioxide is called respiration. The organ system that helps in respiration is called the respiratory system. This system has the following parts: 1) A nose with a pair of openings called nostrils. 6 2/17/2018 4:03:49 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 144

2) Windpipe (Trachea) 3) A pair of lungs: The sac-like lungs are located in the nose chest. They are protected by the rib cage. They mouth occupy most of the space in the chest. Both lungs are not of the same size. The left lung is smaller than windpipe the right. lungs 4) An elastic diaphragm: It is a dome-like muscle diaphragm below the lungs. It separates the lungs from the the human respiratory system stomach and intestine. Understanding How does respiration take place? breathe in breathe out There are two main steps of respiration: 1) breathing in (inhale) oxygen into the lungs 2) breathing out (exhale) carbon dioxide from the lungs The diaphragm has an important role. Breathing in and breathing out happen due to the up and down movement of the diaphragm. It moves down to take in oxygen. It moves up to release the carbon dioxide from the lungs. Application BREATHING RATE running makes us breathe faster Place your hands on your chest as you breathe. What is the pace of your breathing? Now stand and jump for five minutes. Keep your hands again on your chest. You are breathing hard and fast now. Why does this happen? We need to breathe because we need oxygen for many of our body functions. When we run, jump or play, we need more oxygen. So we breathe faster than usual. According to the difficulty level of the activity, the number of times we breathe also increases. The faster we move, the faster we breathe. Respiratory System 7 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 145 2/17/2018 4:03:49 PM

Usually, adults breathe about 18 times in a minute. Children breathe even faster. Count how many times you breathe in a minute. BLOWING air TO Warm UP OR COOL DOWN things Your mother has given you hot milk to drink. But you are getting late for school. What does she do? She blows into the glass of milk to cool it faster. We blow to cool the hot food or drink. The air from the mouth is cooler than the food. So it cools down the food. Does blowing always make things cold? Think, what will happen if you blow on an ice cream? Will it become colder? Try it. Why is the woman in the picture blowing on the fire? a woman blowing into a chulha Wood or fuels need air to burn. So, blowing into the fire makes the fire to burn faster and hotter. Amazing Facts Our body can withstand up to three weeks without food and one week without water. But, we can live only for three to four minutes without oxygen. Higher Order Thinking Skills (H.O.T.S.) Whenever we go to doctors, they keep a stethoscope on our chest. Then he or she asks us to take long breaths. Do you know why? A stethoscope is an instrument used to hear sounds of heartbeats and breathing. Doctors use it to check the health of our body. Our breathing and heartbeats change when we are unwell. stethoscope 8 2/17/2018 4:03:49 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 146

Lesson Nervous System 3 Let Us Learn About r parts of the nervous system. u working of the nervous system. a role of our sense organs. h how the brain works with closed eyes. Think If we happen to touch or hold a hot vessel in our hand, what do we do? We let go of it immediately. How do we come to know that the vessel is hot and we should drop it? Remembering Our body is made up of organs which help us perform various functions. Do you think they perform these functions on their own? How do we walk? How do our legs move to walk? Our body has an organ system which controls all the body functions. It is called the nervous system. Without this system, our brain would be like jelly. It wouldn’t be able to perform any function. Let us learn about the different parts of the nervous system. NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 147 9 2/17/2018 4:03:49 PM

1) The brain: The brain is located in the brain head. It is soft like jelly. It is covered and spinal cord protected by the skull. The skull is very hard. It protects the brain. The brain nerves manages the entire body, but weighs only about 1.5 kg. the human nervous system 2) The spinal cord: It is long and thin like a pipe. It starts from the lower part of the brain. It looks like a long tail of the brain. Along the way, nerves branch out from the spinal cord just like the branches of a tree from a tree trunk. The backbone encloses the spinal cord. 3) Nerves: The nerves are like wires. They are spread in our entire body like a spider’s web. They connect different body parts and organs to the spinal cord and to the brain. Understanding Our nervous system is like a postal service. Through the given pictures, let us understand how the nervous system works: 1) Sender (any organ or body part) gives the message to the postman (nerves). 2) Postman takes the message 1 2 3 (box) through the spinal cord (red scooter). 3) Postman gives the message to the brain. The brain reads these messages and decides what needs to be done. Accordingly, it gives messages in return. The brain tells what to do about the message. 4) The postman (nerves) returns 45 with the message from the brain through the spinal cord. nervous system working like a postal service 10 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 148 2/17/2018 4:03:49 PM

5) Nerves then give the message to the receiver (same or different organ or body part). Once the body parts receive the message, they do what the message asks them to do. In our nervous system, the message can be about different parts of the body or about what is happening outside the body. The brain is the control centre of the body. The brain talks to the entire body through the spinal cord and nerves. It tells our body ‘what to do’ and ‘when to do it.’ All these steps take place at extremely high speed. This is why we can respond to things very fast. For example, when we see something in front of us, within a second we know what it is, how it looks like and how far or close it is. Application To control our body, the brain also needs to know what is happening outside our body. For example, when we walk, the brain needs to get the messages about the things in our way. How does the brain get these messages? For this, the sense organs work along with the nervous system. Eyes, ears, nose, tongue and skin are the organs that help us to sense the things around us. With the help of these organs, we see, hear, smell, taste and feel the things around us. Let us learn how these organs help us to sense with the help of the nervous system. When an object comes in front of us, the eyes send this information to the brain through the nerves. The brain reads this message and tells us what object it is. That is how we see. Similarly, if we smell or taste something, the five sense organs nose and tongue send a message to the brain through the nerves. Then, the brain tells us what kind of smell or taste it is. It also tells us whether the smell and taste are good or not. In the same way, the skin helps us to feel heat-cold, the rough-smooth and so on. Ears help us to hear with the help of messages from the brain. Nervous System 11 NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 149 2/17/2018 4:03:49 PM

Amazing Facts In the human body, the right side of the brain controls the left side of the body, while the left side of the brain controls the right side. Higher Order Thinking Skills (H.O.T.S.) You have learnt that the five different sense organs help the brain to sense the things around us. Our brain identifies objects when the eyes send messages to the brain. Can the brain identify objects even without the help of the eyes? Let us do an activity. 1) Ask your parents, siblings or friends to keep different food items in different vessels. (This can be done in the classroom using the different tiffins during the lunch break.) 2) Close your eyes while they are putting these food items in the container. 3) Blindfold yourself. 4) Smell each food item. Try to identify it by its smell. 5) Try to guess the food by the feel of the food item. 6) If you could not find it out from the smell or feel, blindfolded child identifying then taste it. food item 7) Make a note of how many food items you could identify. From this activity, you will get to know that our brain can identify things with their smell, taste or feel (texture); even with our eyes closed. 12 2/17/2018 4:03:49 PM NR_BGM_181910050_Maple G5_Textbook Integrated_Term1_text.pdf 150